On January 13th, I experienced failures/time outs when trying it publish/overwrite web layers from ArcPro. Esri noted the disruption on their AGOL Health Dashboard. By the afternoon the issues were marked as resolved.
Today, I am experiencing the same issues again. Is anyone having issues trying to publish or overwrite web layers from ArcPro?
Using version 2.9.1.
Something similar happened to me and it ended up being my project; it somehow got corrupted. I created an entirely new project and that fixed the issue. Give it a try and see if that solves the issue!